Games of chance typically associate a winning event with a specific game outcome. For example, achievement of BAR BAR BAR on the payline of a three reel slot machine might pay 20 credits on a 1 credit wager. To increase player interest, bonus awards, which are won independently of any base game outcomes, are sometimes offered. If a bonus occurs during a base game outcome, the award associated with the bonus is typically paid above and beyond the award based on the base game outcome. Bonuses, in their generic sense, can take many forms.
A “mystery” bonus is a popular bonus award that is so named because players cannot easily discern why the award occurred, as it is completely independent of the game's normal schedule of payments. Typically, in a mystery bonus, a maximum bonus period is defined, often in terms of the number of games played or amount of coin-in. A value within that bonus period is selected, which becomes the mystery trigger. Generally the mystery trigger will be randomly selected between a minimum and the maximum value, but the selection may also be weighted toward a particular portion of the bonus period or selected pseudo randomly. For example, if the bonus period is defined as a period of 200 games played, the mystery trigger may be selected to be triggered at the 117th game. When play commences at the first game of the bonus period, a mystery counter increments a count and continues to increase the count for each game played during the bonus period. The player may know the maximum number of games during which the mystery bonus must be awarded, but the player never knows for certain when the mystery trigger will be satisfied. Mystery bonuses are therefore increasingly likely to be won with each game played.
Bonuses can also be based on game outcome, but are paid over and above a standard game pay table. For instance, as described above, a base game may pay 20 credits on a 1 credit wager for the game outcome of BAR BAR BAR. Oftentimes, bonuses are implemented to give the player an additional incentive to play in a particular location or at a particular time. In a game-outcome based bonus, an additional award is provided to the player for achieving a particular game outcome or one of a set of outcomes. For instance, a casino may run a promotion during which the BAR BAR BAR outcome pays an additional 5 credits on a 1 credit wager. The winning player would then be awarded the 20 credits from the standard base game paytable, as well as an additional 5 credits bonus for playing during a special bonus period. A casino may offer bonus periods to promote play during typical slack periods, for example on weekday afternoons.
The amount of a bonus award can also take many forms. In a simple implementation, like the one described above, the bonus is a static award, 5 credits in this example. A progressive bonus, conversely, is one that increases over time during the bonus period based on the amount of each wager made during the bonus period until the progressive award is finally won. In a standard progressive, a small portion of each wager funds a progressive pool. Generally many gaming devices are coupled together and all contribute a small portion of their wagers to the pool, so that the progressive award grows with each wager placed on any of the connected gaming devices. The pools may be formed of a relatively few coupled gaming devices, all of the gaming devices in a single casino, all of the gaming devices in a multi-property casino, and in, some instances, all of the gaming devices within an entire gaming region. The current amount of the progressive pool is typically advertised to the player on a display, which continuously changes as the amount in the progressive pool grows.
Winning a standard progressive is usually based on game outcome. In such a system, a particular game outcome, such as JACKPOT JACKPOT JACKPOT is selected as the progressive trigger. When a player hits the base game outcome, he or she wins the base game award and additionally is credited with the amount of the progressive. Usually the progressive trigger is selected as one that is infrequently won, so that the progressive award grows for a relatively long time, and reaches a relatively high value before it is won. This builds excitement for players and incentivizes them to play the games coupled to a progressive bonus.
A progressive award may also be triggered in the “mystery” fashion described above, and not based on game outcome. In a mystery progressive a bonus period is defined by a starting and ending (maximum) value. The award must be won before the award grows larger than the maximum value. A winning amount W is randomly selected from within the range of all values between the starting and ending award values. For example, a mystery progressive starts at $1,000.00 and ends at $5,000.00. A winning value W is chosen from the range of numbers between $1,000.00 and $5,000.00. For example, W may be chosen to be $2,431.56. The progressive award value is initially set to the starting value of the award range, $1,000.00, and increases with each wager as a function of the wager size. A commonly used embodiment adds a percentage of each wager amount, for example, 3% of wager size. For example if a player wagers $3.00, 3% of the wager, or 9 cents, is added to the progressive award so that the current value grows to $1,000.09. The current award amount is then tested against the current value of W. Since $1,000.09 is less than $2,431.56, the test fails and the player does not win the mystery progressive.
This process continues until cumulative play brings the award to $2,431.56, making the comparison to the previously selected winning amount, W, true. When the mystery trigger is satisfied, the player who made the wager that satisfied the trigger is identified and awarded the mystery progressive.
A problem exists in that, directly after a progressive award is won, the reset starting amount is lower, and typically much lower than the large number that had just been displayed and won. For example, a large progressive may have risen to over $100,000 before being won, and, after being won, resets to $1000. The incentive to play for a chance to win $1000 is obviously much lower than the incentive to play for a higher amount. This is true both in game-outcome-based triggers, where the likelihood of winning is the same with each game played, as well as in mystery-based triggers, where the likelihood of winning is actually lower at the beginning of a mystery period compared to the end of the period. Embodiments of the invention address these and other limitations in the prior art.